基于新型Padé近似BPM算法的TE模式分析

针对光束传播法中使用(p,p)阶的Padé近似方法求解模式时,由于将消逝模和传输模统一对待而造成的无法很好地抑制消逝模对仿真结果影响的问题,本研究提出采用基于(p-1,p)阶Padé近似算法来提高波导TE(transverse electric)模式的数值仿真精度的方法。实验结果表明,基于这种新型近似算法的光束传播法在波导仿真中对消逝模可以起到有效的抑制作用。

TE mode analysis based on a new Padé approximant BPM algrorithm

The most common method used in the wide angle BPM(beam propagation method)was the (p, p) Padé approximant formalism, which could not damp the evanescent modes for the algorithm itself. A new BPM based on a direct approximation to the propagator using (p-1, p) Padé approximant was applied to tapered waveguide for TE polarized waves. Based on the results of the new method, it was found that the new method of (p-1, p) Padé approximant could obviously suppress the evanescent modes in TE mode, and could be more accurate to the propagating modes with the increase of p.